Sebastian Schaffert – författare

The best informal de?nition of the Semantic Web is maybe found in the May 2001Scienti?cAmericanarticle“TheSemanticWeb”(Berners-Leeetal. ),which says“TheSemanticWebisanextensionofthecurrentWebinwhichinformation is given well-de?ned meaning, better enabling computers and people to work in cooperation. ” People who work on the Semantic Web quite often base their work on the famous “semantic web tower”, a product of Tim Berners-Lee’s inspiring drawing on whiteboards. The lowest level is the level of character representation (Unicode) and the identi?cation of resources on the Web (URIs). The highest level concerns the problem of trusting information on the Web. Somewhere in the middle of the tower is the logic level. It addresses the problem of represe- ing information on the Web in a way so that inference rules can derive implicit information from explicitly stated information. The workshop “Principles and Practices of Semantic Web Reasoning” (PPSWR 2004) addressed problems on this level. It took place in September 2004 as a satellite event of the 20th Int- national Conference on Logic Programming (ICLP) in St. Malo, France. After PPSWR 2003 in Mumbai, India, it was the second workshop in this series. This book contains the articles presented at the workshop.

The best informal de?nition of the Semantic Web is maybe found in the May 2001Scienti?cAmericanarticle“TheSemanticWeb”(Berners-Leeetal. ),which says“TheSemanticWebisanextensionofthecurrentWebinwhichinformation is given well-de?ned meaning, better enabling computers and people to work in cooperation. ” People who work on the Semantic Web quite often base their work on the famous “semantic web tower”, a product of Tim Berners-Lee’s inspiring drawing on whiteboards. The lowest level is the level of character representation (Unicode) and the identi?cation of resources on the Web (URIs). The highest level concerns the problem of trusting information on the Web. Somewhere in the middle of the tower is the logic level. It addresses the problem of represe- ing information on the Web in a way so that inference rules can derive implicit information from explicitly stated information. The workshop “Principles and Practices of Semantic Web Reasoning” (PPSWR 2004) addressed problems on this level. It took place in September 2004 as a satellite event of the 20th Int- national Conference on Logic Programming (ICLP) in St. Malo, France. After PPSWR 2003 in Mumbai, India, it was the second workshop in this series. This book contains the articles presented at the workshop.

The Reasoning Web summer school series is a well-established event, attracting experts from academia and industry as well as PhD students interested in fo- dational and applicational aspects of the Semantic Web. This volume contains thelecturenotesofthefourthsummerschool, which took place in Venice, Italy, in September 2008. This year, the school focussed on a number of important application domains, in which semantic web techniques have proved to be p- ticularly e?ective or promising in tackling problems. The ?rst three chapters provide introductory material to: - languages, formalisms, and standards adopted to encode semantic information; - "soft" extensions that might be useful in contexts such as multimedia or social network applications; - controlled natural language techniques to bring ontology authoring closer to end users. The remaining chapters cover major application areas such as social networks, semantic multimedia indexing and retrieval, bioinformatics, and semantic web services.Thepresentationshighlightedwhichtechniquesarealreadybeingsuccessfully applied for purposes such as improving the performance of information retrieval algorithms,enablingtheinteroperationofheterogeneousagents,modellinguser's pro?les and social relations, and standardizing and improving the accuracy of very large and dynamic scienti?c databases. Furthermore, the lectures pointed out which aspects are still waiting for a solution,andthepossiblerolethatsemantictechniquesmayplay,especiallythose reasoningmethodsthathavenotyetbeenexploitedtotheirfullpotential.Wehope thatthe school'smaterialwillinspire further exciting researchinthese areas. We are grateful to all the lecturers and their co-authors for their excellent contributions, to the Reasoning Web School Board, and Norbert Eisinger in particular, who helped in several critical phases, and to the organizations that supported this event: the University of Padua, the MOST project, and the N- work of Excellence REWERSE.

The book at hand re?ects on the increasing convergence of Social Media and Semantic Web technologies. It was the editors' intention to collect - to-date and high quality contributions that illustrate various approaches to this young and emerging technology area. To guarantee this we invited be- of authors from the international conferences I-SEMANTICS and I-KNOW from the years 2007 & 2008 that took place in Graz / Austria to prepare - tended contributions that illustrate this agile and fast-evolving development and hint at trends that might accompany us for the years to come. More than 60 authors from 12 countries with either academic or industrial ba- ground provided us with 20 articles covering a broad range of topics related to frameworks, applications and concrete use cases. After more than a year of preparation we would like to thank all authors for sharing their experiences and insights with the reader. We also would like to thank them for their motivation, dedication and creativity uncompla- inglyincludingourfeedbackintotheircontributionstherebyensuringthehigh qualityofthebook.SpecialthanksalsogotoGiselaGranitzerfromtheKnow Center in Graz who accompanied the editorial process with valuable c- ments and contributionsand helped us to ?nally bringing this volume to you. Have an inspiring reading! Vienna, March 23, 2009 Tassilo Pellegrini S.. oren Auer Sebastian Scha?ert Klaus Tochtermann Contents Introduction NetworkedKnowledge-NetworkedMedia:-Bringingthe PiecesTogether...1 Tassilo Pellegrini, Sor .. en Auer, Sebastian Scha?ert, Klaus Tochtermann FrameworksandInfrastructures RDFSupportintheVirtuosoDBMS...7 Orri Erling, Ivan Mikhailov Semantic Task Management Framework: Bridging InformationandWork...25 Ernie Ong, Uwe V. Riss, Olaf Grebner, Ying Du AUTOMS-F:AFrameworkfortheSynthesisofOntology MappingMethods...